A great number of various viruses are stated as the cause of acute infections and damages of the central nervous system. In most cases these are minor damages which exhibit as meningeal syndrome and a specific finding in the cerebrospinal fluid. According to the dominant location, central nervous system infections can take a form of meningitis, encephalitis or myelitis. Since the inflammatory process of the meninges can not be separated from the inflammatory process of the brain, we usually speak of meningoencephalitis. The etiological diagnosis of meningitis and encephalitis is established by isolating the virus from the cerebrospinal fluid and by finding the presence of the specific antibodies in the blood and in the cerebrospinal fluid. The most common causes of the viral meningitis are Enteroviruses, the Mumps virus, Arthropode borne viruses, the Herpes viruses, Adeno viruses and the Lymphocytic choriomeningitis virus. The aim of our study was to establish the correlation between the clinical features and immunological and cerebrospinal fluid changes and the degree of the damage to the blood-brain barrier during the infections of the central nervous system, caused by the Herpes Simplex virus and the Lymphocytic choriomeningitis virus.
From a group of 103 patients, who had been treated for viral meningitis and meningoencephalitis, a group of 27 patients with established specific viral etiology--Herpes Simplex virus and Lymphocytic choriomeningitis virus, had been taken into the account. Herpes Simplex infection had been proven by the complement binding reaction and the neutralisation test of the even samples of serum. The diagnosis of Lymphocytic choriomeningitis was confirmed by the immunofluorescence test of the pharynx swabs and cerebrospinal fluid. The clinical features, such as body temperature, encephalitic signs, and electroencephalographic findings had been followed and compared.
Herpes Simplex infection had been found in 20 patients, Lymphocytic choriomeningitis had been proven in 7 patients. All the patients had increased body temperature. Only four of the patients exhibited encephalitic signs, all infected by the Herpes Simplex virus. Patients from the Herpes Simplex group showed various degrees of consciousness disturbances, ranging from somnolence to coma, while the Lymphocytic choriomeningitis patients exhibited none. Higher pleocytosis and protein level had been found in the Lymphocytic choriomeningitis group.
Viral diseases of the central nervous system are the result of the direct damage of the brain and meninges by the virus and immunological processes. Herpes Simplex meningitis usually has a good prognosis. Lymphocytic choriomeningitis has longer course of the disease and exhibits more severe clinical features.
In cases of the central nervous system infections, caused by Herpes Simplex virus or Lymphocytic choriomeningitis virus, the correlation between the severeness of clinical features and the degree of damage of the blood-brain barrier, the level of pleocytosis and the increase of the cerebrospinal fluid proteins had been established.